Electric Shock using headphones

RandomCake

Hi All,

I was sitting still in bed browsing the web and listening to music on my laptop and just had an electric shock from my headphones, the laptop is connected to the mains, and the shock was quite strong (I think it was too strong to have been static, didn't really feel like static, and as everything I'm wearing is cotton that seems unlikely!)

Has anyone experienced this? I don't really want to get into experimenting with this! Is it likely to be the headphones fault, the laptops, or a mixture of the two?

I use the headphones daily for at least an hour with my phone and haven't experienced this before, but have used it with the laptop now and then in the past...

These are the headphones:
http://www.amazon.co.uk/gp/product/B000V5L5MG

And here is my laptop (makes me feel sick to see how much cheaper it is only a few months on!):
http://www.dixons.co.uk/gbuk/acer-aspire-5745g-refurbished-laptop-06219051-pdt.html?srcid=198&gclid=CLuRrZOwtqgCFYob4QodJ0M1Bw

Any advice gratefully received!

Tom

asbokid

Have any fluids got into the laptop charger? Do you sleep heavily? Are you a wetter?

RandomCake

Nope, not a wetter, I was wide awake at the time, and the charger is sound (and isn't it likely that the laptop its self would be fried if the charger were the issue? Although I guess my ears might have been a good place to earth a surge and protect the motherboard!)

fwor

Almost certainly static, from days of dry weather. A mains shock doesn't feel "quite strong" - it's generally very unpleasant.

The laptop runs off around 20V DC, which you won't feel unless doing something daft like putting your tongue on it! If the charger were faulty and putting out much too high a voltage then the laptop would have stopped working.

RandomCake

I hope you're right, I'll just have to start using headphones instead of earphones until it starts being cold and miserable as it's supposed to be in England!
Does this cause problems for much drier countries?

Tom

fwor wrote: »

Almost certainly static, from days of dry weather. A mains shock doesn't feel "quite strong" - it's generally very unpleasant.

The laptop runs off around 20V DC, which you won't feel unless doing something daft like putting your tongue on it! If the charger were faulty and putting out much too high a voltage then the laptop would have stopped working.

RandomCake

I dropped this as it sounded like I was mistaken, but now I'm getting shocks again in the right ear piece, but if I put the left in my ear it's fine, *but* when I've brushed my arm on the right ear piece I've felt a small shock.
I have felt mains shocks a few times in my life, so I know how horrible it feels. But we're not talking about a direct mains connection, we're talking about a pair of earphones, which I sure don't receive that much current!
Is it likely that static would be building up when the damn thing wasn't even in my ear?

kwikbreaks

Look at this logically...

If you are getting a mains shock then for that to happen you must have...

A faulty laptop charger for the mains to get on the output
+
A faulty headphones for the mains on the socket to get through the cable and headphone itself to your head.

Bogtrotter

Is it an instantanious shock or more continuous shock?

Does the mains cable connect to the laptop power supply with a 3 pin IEC or similar or is it a two pin figure 8 connector or similar?

esuhl

I'm not sure, but I would have thought that the current that earphones use to generate sound is tiny - anything powerful enough to give you a shock would rip the cone in the 'phones (meaning that they wouldn't work again) with a loud pop.

Is it possible that a static charge has built up on the plastic of the earphones and is being earthed by your ear? Or is there a sharp piece of the earphone that suddenly sticks in giving you a shooting pain that feels like an electric shock?

To isolate the problem: does it occur if you connect the earphones to a different source, or if you use a different pair of earphones with the laptop?

s_b

get everything pats tested tomorrow before something serious happens

Bogtrotter

esuhl wrote: »

I'm not sure, but I would have thought that the current that earphones use to generate sound is tiny - anything powerful enough to give you a shock would rip the cone in the 'phones (meaning that they wouldn't work again) with a loud pop.

Its not the voltage of the earphone but the difference between the connections of the earphone... one could be 1000 volts and the other could be 1001 volts and the earphone could be working happily but as soon as you stick it in your ear.... ZAP

Just a guess from me but if its not a static "instantaneous" shock the "problem" is probably a poor earth on the electrical system.

If I had to guess some more the laptop power supply is a 3 pin meaning the chassis of the laptop is connected to the installation earth. Since the earth is bonded to the neutral... if you have a poor earth on the installation could mean that the neutral (and hence the chassis) is floating a little higher than 0 volts of the real earth. This is what's giving the electric shock but there is very little current so not dangerous in itself.

For example I have a similar issue with my house in France... I estimate the neutral is 50 volts compared to earth and you can sometimes feel the electricity when you brush against the washing machine when walking on bare feet.

Quick fix is to buy one of the universal laptop adapters which aren't earthed... that should isolate the laptop from any problem due to poor earth.